The invention relates to a backlight luminaire for a display device, which luminaire comprises a plurality of fluorescent lamps and a reflector which includes a plurality of sub-reflectors.
The invention also relates to a liquid-crystal display device which includes a backlight luminaire.
Backlight luminaires are used as a light source in flat-panel type display devices, in particular liquid-crystal display devices (LCD devices).
Fluorescent lamps are very suitable for use as light sources in flat-type display devices because they have a high light output and the spectral characteristic of the light emitted can be adapted in a simple manner. In such display devices, a luminaire, which is arranged behind the display, is generally provided with elongated fluorescent lamps which are arranged in parallel relation to each other. It is alternatively possible to use U-shaped fluorescent lamps or so-called meander-shaped fluorescent lamps.
GB A2 207 496 discloses a backlight luminaire which is used as a light source for a liquid-crystal display (LCD) device, which luminaire includes a plurality of U-shaped fluorescent lamps which are alternately arranged at the back of a liquid-crystal display device. On the side of the backlight luminaire facing away from the liquid-crystal display device, there is provided a reflector including reflectors or an assembly of sub-reflectors. In general, the (sub-)reflectors are concave in shape. In the known backlight luminaire, one of the arm portions of one of the U-shaped fluorescent lamps is inserted between the arm portions of an adjacent lamp or lamps so as to be parallel thereto.
In general, it is desirable that the light source(s) in backlight luminaires should uniformly illuminate the active part of the display device.
A disadvantage of the known backlight luminaire is that if one of the (U-shaped) fluorescent lamps emits less light or light having a different spectral characteristic, or if one of said fluorescent lamps fails, there is a locally non-uniform light distribution at the location of the relevant lamp.